A sweet female who knows how to talk to a male, and is usually quiet, smart and doesn't talk too much, but is ignored by them because she is not as attractive as the smug bitches wearing thongs. Like nice guys, but female.

The nice girl was very sweet and would never disrespect a man, but she was ignored by the boys because they would rather have a moronic bitch that's hot than a smart, sweet one who's not the hottest thing in the world.

A girl that is generally nice. She hangs out with a majority of guys and plays video games and is basically one of the guys. But she can also be girly and do girl things; shop, makeup, ect. But for some reason can never get a boyfriend. One, because the guys seem to only see her as one of the guys and she never gets noticed. Two, she sticks arounds listening to all her guy friends problems with their current sluts and gives advice. Three, she is always taken for granted and lets herself be taken for granted, hoping that one day a guy will notice how wonderful she really is. But that will obviously not happen anytime soon since all guys seem to be attracted to are easy girls, with caked on makeup, skimpy clothing, and probably a million unknown STDs.

-Dude Jen is so good at guitar hero!
-Yah i know! and she's a pretty nice girl.
-you're right maybe you should ask her out
-Fuck no she's like one of the guys!

1. The self-labeled female equivalent of the “Nice Guy”. A woman who will spend most of her time whining about how men “just want to date sluts”. Oblivious to the fact that no one finds people who feel sorry for themselves attractive, much less people who blame others for their lack of success. To stupid to figure out why men don’t find them attractive, they conclude that in order to be in a relationship they must act promiscuous and trashy.

They tend to befriend men who are already in relationships (sometimes who are in relationships with other men! Or who are married!). Often misrepresenting their intentions and trying to use emotional manipulation and the facade of friendship as an excuse to get closer to the man and start a relationship with him.

2. Sometimes, however nice girl just means a girl who is sweet and kind. And thus, has no negative meaning like my definition #1.

1. Nice Girl: How come won’t you date me?
Her male friend: Because, I already have a boyfriend!

The name that's commonly used for a certain girl named Jessica Hall. This does not necessarily mean she is a "nice girl" because of the lack of the space in between "nice" and "girl", and should not be used as in "she's a nice girl", but as in "she's Nicegirl"
It is a proper noun and has been linked with Jessica Hall for almost 3 years.
Given to her by Tyler Gunn and Nate Irvin, and some other guys that were there at the time

Nicegirl- "Hey! I got my tits signed by Dani Filth and partied all weekend!"
Guy- "I thought you were supposed to be a nice girl?"
Some other person- "Retard, her NAME is Nicegirl she's not a nice girl!"